US-based Aussie actress Robin McLeavy has thrown her support behind calls to conserve the Great Barrier Reef.

Ms McLeavy, who appears in the hit show 'Hell on Wheels', spent Tuesday in Port Douglas interviewing concerned residents for a short documentary she is filming.

The actress says she'd like the documentary to inform people about the impact of major dredging proposals throughout Queensland.

"I think educating Australians about what the long-term effects can be helps us appreciate how fragile the ecosystem is," Ms McLeavy says.

Around three million cubic metres of dredging spoil will be dumped near the Great Barrier Reef as part of plans to expand the coal terminal at Abbot Point near Gladstone.

The dredging, approved by Federal Environment Minister Greg Hunt, will occur near Bowen in north Queensland.

The State Government has also flagged its intentions to dredge Trinity Inlet near Cairns in the future.

Documentary producer Jodie Passmore says not enough people understand the impact dredging will have on the Great Barrier Reef.

"There seems to be a huge disconnect between what people know and what is actually happening on so many levels," she says.

"So we thought what can we do and decided to come up here and see what we can make."

Ms McLeavy says visiting Port Douglas was a 'dream come true'.

"This is my first time up here and I've always wanted to come up to the Great Barrier Reef since I was a little kid," she says. 

The filmmakers says they plan to release the documentary online.

Ms McLeavy says she hopes it makes a difference.

"I get really frustrated when I see what's happening over here with the reef," she says.